1. Field of Use
The present invention relates to sialosyl cholesterol, in particular sialosyl cholesterol which is useful as an agent for treating various diseases derived from lesions of peripheral nerves and central nerves.
2. Description of the Background
So far, it has been known in the art that sialic acid is present in many animal bodies and on the cell surface of several bacteria as a sialylated molecular complex, for example, glycoprotein, glycolipid, oligosaccharide or polysaccharide.
Recently, this compound has been thought to be important medicinally and pharmaceutically for nerve function, cancer, inflamation, immunity, viral infection, differentiation, hormone receptor, and others. Further, much attention has been paid to this compound as a peculiar active substance located on the cell surface. However, the role of sialic acid in the sialylated molecular complex has not yet been ascertained.
Furthermore, this compound has been studied by many natural organic chemists and many kinds of derivatives thereof have been obtained. However, no derivatives having a remarkable physiological activity have been obtained yet.
Further, the average span of human life has been indeed extended by various improvements in medical treatment of malignant tumor of hematopoietic organ, many kinds of cancers, and collagen disease. However, these improvements have inevitably increased use of medicines such as adrenal cortical hormone, immunosuppressant, etc. Therefore, a number of undersirable side effects such as decrease in immunological competence have arisen.